The present invention relates, in general, to brake shoes and brake heads for railway vehicles; i.e., railway cars, transit cars and locomotives and, more particularly, the present invention relates to a keyless attachment of a brake shoe to the brake head.
Railway vehicles traditionally use a braking system wherein a brake shoe is forced against the wheel surface of the vehicle to provide a retarding force. The brake shoe is mounted to a brake head that is used to locate the brake shoe and provide the braking force to the brake shoe.
These railway brake shoes are typically mounted on such brake rigging of railway vehicles by means of a brake shoe key, which passes through a longitudinal slot in the brake shoe holder or brake head of the brake rigging and concurrently through mounting holes of the brake shoe backing plate. Such holes are normally located in a central xe2x80x9ckeybridgexe2x80x9d area of the brake shoe backing plate. The keybridge area of the backing plate is generally formed in such a way that it is adapted to protrude into or intersect with a longitudinal slot in the brake head at or near the center of the brake head""s length. Thus, the shoe is held in place in the brake head by this key that passes through openings in the brake head and the brake shoe as is seen in FIG. 1.
The brake shoe keys that are used to retain the brake shoes have a history of problems including not only working loose due to vibration but also breaking while in service. If either of these problems occur then the brake shoe will not be held in place properly and will not contact the wheel properly and more likely the brake shoe will fall off. If the brake shoe falls off then the brake head will contact the wheel during a brake application which results in both an unsafe brake application and possible detrimental damage to both the wheel and brake head. Further, the use of these brake shoe keys means that these keys must be kept in inventory and thus be available to maintenance personnel for attaching a new brake shoe.
The present invention provides a brake shoe adapted to engage the tread of a railroad car wheel via which such railroad car is guidably supported on a railed track. The brake shoe comprises a backing plate which has a predetermined configuration and a means disposed adjacent each end of the backing plate for securing such backing plate to a brake head. The brake shoe further includes a brake lining that is affixed to the backing plate and has a braking surface engageable with the wheel tread of a railroad car wheel.
Accordingly, it is a primary object of this invention to provide a new and improved brake shoe for railway vehicles having improved means for securing the brake shoe to the brake head.
Another object of this invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head can be formed integrally as a portion of the backing plate of such brake shoe.
Yet another object of the present invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head can be welded to the backing plate.
It is still another object of the present invention to provide a specially configured spring clip to secure the brake shoe to the brake head.
Another object of this invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head can minimize damage to brake heads and wheels.
Still another object of the present invention is to provide a brake shoe for railway vehicles wherein the specially configured spring clip can reduce inventory.
Yet another object of this invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head which will be cost effective.
Another object of this invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head can be retrofitted to existing brake heads.
Still yet another object of this invention is to provide a brake shoe for railway vehicles wherein the means for securing the brake shoe to the brake head is easier to install.
These and other objects and advantages of this invention will become apparent after a full reading of the following detailed description, particularly, when read in conjunction with the attached drawings as described below and the appended claims.